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Dynamic Mechanical Analysis
Duncan PriceIPTME, Loughborough University© Copyright: [email protected] (2006)
mechanical testing
dynamic mechanical analysis
relationships
test configurations
Rubbery plateau is related to Me between cross-links or entanglements
Tll in some amorphous polymers
Tm = melting (1)
For thermosets, no Tm occurs
Rubbery plateau (2)
In semicrystalline polymers,a crystal-crystal slip, T* occurs
For purely crystalline materials, Tg occurs
Tg is related to molecular mass up to a limiting value
transitions are often related to the toughness
typical behaviour
polycaprolactone
impact resistance in nylon
material specification
thermoset cure
determination of Tg
effect of plasticiser
stress relief
PET
effect of frequency
frequency domain
frequency master curve
effect of molecular weight
gellation of polymer solution
thermoset curing
Gillham-Enns or TTT diagram
recommended reading
M. Reading and P.J. Haines; “Thermomechanical, dynamic mechanical and associated methods” in; P. J. Haines; “Thermal methods of analysis: Principles, Applications and Problems” Blackie, London (1995) pp.123-160.
K.P. Menard; “Dynamic Mechanical Analysis: A Practical Introduction to Techniques and Applications”, CRC Press, Boca Raton (1999)
D. M. Price, “Thermomechanical and Thermoelectrical Methods”, in P.J. Haines (ed.) Principles of Thermal Analysis & Calorimetry, ch. 4, Royal Society of Chemistry,
Cambridge (2002) pp. 94-128.
